Pressure compensated valve device for well tools



Aug. 4, 1953 PRESSURE COMPENSATED VALVE DEVICE FOR WELL TooLs Filed July 7,

B. KRIEGEL 2,647,583

2 Sheets-Shea?l l Aug- 4, 1953 B. KRIEGEL 2,647,583

PRESSURE COMPENSATED VALVE DEVICE FOR WELL TOOLS Filed July 7. 1947 2 Sheets-Sheet 2 Arme/vir.;

Patented Aug. 4, 1953 PRESSURE COMPENSATED VALVE DEVICE FOR WELL TOOLS Bernard Kriegel, San Francisco, Calif., assign'or to Baker @il Tools, Inc., Vernon, Calif., a corporation of California Application July 7, 1947, Serial No. 759,321

12 Claims.

This invention relates to well tools, and more particularly to valve mechanisms forming part of such. tools, especially employable in connection with the cementing, acidizing, washing, production, etc., of oil and gas wells.

'Some forms of sub-surface well tools used in the cementing of a well bore embody a valve device which is subject to the pressure of the fluid in the tubing string connected to a well tool, of whichthe valve device forms a part. The iuid pressure differential within the tubing string and well tool over the external pressure 'tends to vmaintain thevalve device is closed position, and vrenders it diiicult to move the valve to open position when desired. As an example, ia valve member which moves downwardly into seating engagement with a cooperable valve seat is subjected to `a hydrostatic head of cement slurry within the tubing string tending to keep the valve member in closed position and preclu'ding its movement to open position.

Some forms of well tools of the character indicated may be used in connection with the swabbing of the well bore. However, the valve device, land particularly a downwardly seating valve device, may be inadvertently shifted to open position upon the creation of a suction eiect in the tubing Ystring attached to the well 'tool or within the well tool itself, thereby preventing the desired swabbing effect from occurring.

Accordingly, it is an object of the present invention to provide a valve device in a well tool, in which tbe effects vof pressure thereon tending to` produce and maintain its closing are largely minimized.

Another object of the invention is to provide a well tool valve device adapted to be moved between open and closed position without restraint o1' interference by fluid pressure within the tool,

"hing operation can be performed without hazard of pressure diierentials inadvertently opening a control valve in said tool.

This invention has other objects that will become apparent from a consideration of the embodiments shown in the drawings accompanying and forming part of the present specification.

These'forms will now be described in, detail, buty 2 it is to be understood that such detailed description is not to be taken in" a limited sense, since the scope of the invention is best 'defined by the claims appended hereto.

Referring to the drawings:

Fig. 1 is a longitudinal section through a well tool located in a well casing, with its valve device in open position.

Fig. 2 is a 'longitudinal'section on an enlarged scale through the valve device, whose parts are illustrated in open position'.

Fig. y3 is a view similar to Fig. 2, with the valve device closed.

Fig. Il is aside elevation of the lock device for holding the valve mechanismin a predetermined position.

Fig. 5 is a view similar to Fig. 2 of a modified form of valve device.

The invention is disclosed in the drawings as applied to a well packer of `a type designed to force uid under pressure thrcugh'the perforations of a well casing. It is to `be understood, however, that it has application to any type of well tool, through or from which iiuid flow is to be controlled.

Specically, the well tool consists of a body I0, suitably secured as by threading to the lower end of a string of tubing or drill pipe I I, by means of which the tool is yconveyed. through the well casing I2 to the desired operating point therein. The body consists of an upper body member I3, a lower body member I 4, and an intermediate body member I 5 connecting the upper and lower members together in spaced relation. The general type of welltool shown is a packer described Vand claimed vin the application of Charles E.. Costello, Serial No. 391,548, led May 2, 194i, for Well Devices, now Patent No. 2,466,305.

The upper and'lower portions of the tool are substantial duplicates, being connected to the intermediate body member l5 in opposed relation. A descriptionof the upper portion should suffice for the lower portion as well.

The upper body member 'I3 includes an velongate mandrel or nipple i6 having a sub I1 screwed on its upper end, and a lower ported .subV

i suitably secured on the mandrel, with the lower An upper by-pass tube 2G is positioned within the upper body member to provide an annular space 2l therewith. Its upper member is threaded into a by-pass T 22, which is suitably secured, as by welding, to the upper by-pass sub Il, through which it opens outwardly into the tubing-casing annulus 23 above the upper packing Si. The lower end of the by-pass tube 20 extends through an inner flange 24 on the lower sub I8, containing a rod packing 25 pressed in leakproof engagement against the exterior of the tube by a suitable packing nut 25, to prevent downward flow of uid through the annulus 2l beyond the flange 24.

As stated above, the construction of the lower tool portion is substantially the same as the upper, with the parts facing in the opposite direction, so that fluid passage between the lower body member I4 and casing wall in both upward anddownward directions is prevented, and upward flow of lluid through the lower annulus 2id beyond the ange 24a is prevented by the flange 24a, packing 25a and packing nut 26d surrounding the lower by-pass tube 20a. convenience in designation, the lower parts are numbered the same as the corresponding upper parts with the suffix a added.

The upper and lower tool portions are held For,-

together in spaced relation by the intermediate.'

body member l5, which actually forms part of the by-pass of the tool. This intermediate body member is secured to the upper and lower subs I8, I8a and may be made of any length desired,

depending upon the spacing required between the upper and lower packing cups 60, 60a. The

by-pass around the packings extends from a point outside the tool below the lowermost packing Ela to a point outside the tool above the uppermost packing 6I. More specically, this by-pass passage is constituted by the lower T 22a, lower by-pass tube 20a, intermediate body member I5, upper by-pass tube 20, and upper by-pass T 22.

The upper sub I 8 is provided with one or more upper outlets or ports 21 adjacent the packing cup 50 and ange 24, and the lower sub i3d is similarly provided with one or more lower outlets or ports 21a adjacent the lower packing cup 60a and flange 24a. Fluid cannot pass directli7 from the upper body annulus 2| to the lower f body annulus 2Ia because of the flanges and packings around the by-pass tubes, but must pursue an indirect course. The fluid may be pumped downwardly through the tubing I'I into the upper body member annulus ZI, exiting.

through the upper ports 21 into the localized annular Zone 28 defined by the upper and lower packings 60, 50a and by the intermediate body member I5 and casing I2. This uid may ow downwardly through the zone and enter the lower body member I4 through the lower ports 21a, where the uid can pass downwardly through the annulus 2| a around the lower bypass tube 20a into a valve body or housing 29 screwed into the lower end of the lower sub I'Ia. The uid may then pass through the valve outlets or ports 30 in the housing to the exterior of the tool 23a below the lower packing cup Gla, from where it may flow upwardly into the lower by-pass T 22a, through the lower by-pass tube 20a, intermediate by-pass member I5, tube 20, and upper by-pass T 22, into the tubing-casing annulus 23 above the upper packing cup 6|.

The allowing of the uid to pursue the course just described is dependent vupon the Qontrol, 0f

the iluid flow through the valve ports 3G at the lower end of the tool. Such control is obtained through a valve mechanism, including a valve stem 3| within the housing to which a Valve member 32 is secured. The valve stem has a rod extension 33 depending through a lock sleeve 34 threaded into the lower end of the housing 29. The lower end of the rod extension is attached to a drag device, which, in the present instance, consists of a lower collar 35- and guide 36 threaded on the rod with a plurality o outwardly bowed drag springs 3"! secured to the lower collar and extending upwardly for attachment to an upper collar 38 slidably mounted on the rod 33.

The drag device resists movement of the rod extension 33, valve stem or rod 3l and valve member 32 in both longitudinal directions within the casing I2. lThat is, downward movement of the tubing string II and attached body It of the tool tends to move the valve body or housing 29 downwardly with respect to the valve member 32, causing the latter to move relatively in an upward direction which, in the specific design disclosed in the drawings, is its open position. Similarly, elevating of the tubing string II, body il) and valve housing 29 tends to cause the Valve member to move relatively in a downward direction, or to closed position.

The positions of the valve member 32 in the valve housing 29 and with respect to the valve ports 3D are determined positively by a lock device. In the present instance, this device includes a lock pin 39 secured to the rod extension 33 and extending into a lock slot 4U, 4I formed in the sleeve 34. This slot has an upper lateral or transverse portion 40, which will receive the pin 33 and hold the valve member in an upper open position, and with a longitudinal portion 4I which will permit the lock pin to move .lengthn wise of the sleeve 34 and allow the Valve member 32 to move to closed position, as more specifically described hereinafter.

The valve member includes an elongate body 42, whose lower end is threaded onto the rod 3|- This body carries a packing ring or sleeve 43 on its upper portion, which is conned between a lower ring 44, welded to the body, and an upper head 45 threaded on the upper end of the body. The packing member 43 is adapted to be drawn relatively downwardly through a downwardly and inwardly tapered guiding face 4t in the housing 29 into a cylindrical seating surface Il?,

disposed in the valve housing above the port 30, such movement being permitted when the lock pin 39 is in alignment with the longitudinal lock slot 4I in the sleeve 34. The housing is formed as a cylinder 48 below the ports 30, along whose wall 48a a lower annular piston 49, integral with the body 42, may slide, leakage between the annular piston 43 and cylinder wall 43a being prevented by suitable piston rings 50 of rubber, or other appropriate material, in peripheral piston ring grooves 5I.

The valve body 42 is generally tubular in form, having a passage 52 therethrough which can communicate with the annular space 53 between the piston rod 3l and cylinder wall 48a below the annular piston 49 through ports 54 formed through the body below the annular piston. In order to prevent fluid from moving downwardly out of the cylinder space 53, rod packing rings 55 are provided in grooves 5B in the upper portion 5'! of the lock sleeve 34, such packings being in slidable sealing engagement with the rod.

Moreover, a thread seal 58 maybe provided between the upper end of the sleeve 34 and thev cylinder 4B to prevent leakage of lluids vthrough their threaded interconnection. In effect, the upper end 51 of the lock sleeve forms a cylinder head, beyond which fluids cannot pass.

The inside diameter of the cylindrical seating surface lill is substantially less than the vinside diameter of the cylinder 48, with which the annular piston `119 is in slidable engagement. These diameters are chosen so that vthe effective area A across the valve member, when its seal ring or Sleeve '43 is disposed withinthe cylindrical lscating surface 44l, is substantially equal to the annular area B ci the cylinder space 53 between the inner walld oi the cylinder andthe rod `3 l.

When the valve is in closed position, as illustrated in 3, ilu-id under pressure within the tool above the valve member 32 acts downwardly across the effective area A and tends to hold the valve member in such downward closed position. Such iiuid pressure 'is also transmitted through the fluid in the passageway 52, fEll into the annular cylinder `space 53, acting upwardly on v'the piston t9 and lower end of the body 42 across the annular varea B. Accordingly, 'it is seen that;

since the areas A and Bare equal to one another, the fluid pressure force acting in a downward direction and tending to hold the valve closed is equal to the fluid pressure force .acting in an upward direction and tending to move the valve member 32 upwardly, to shift its packing `Mi out of the cylindrical seating surface 4l, or to open position. Thus, the valve member may be moved between open and closed positions with facility simply by 4appropriate manipulation of the tubular string II, the drag springs 3l engaging `the wall of the well casing I2 ywith suiiicient force to tend to hold the valve member 32 stationary and allow the valve housing 29` and remainder of the well tool to be shifted longitudinally thereof.

One representative use of the valve mechanism in question is in connection with the cementins of a casing. The tool disclosed in Fig. 1 is .lowered through the well casing I2 until the inner packing cups 6U, 50a are disposed on opposite sides of casing perforations 59, through which cement slurry, or other cementitious material, is to be ejected. During this running-.in operation, the drag springsl resist lowering of the valve member 32 within the casing, and, accordingly,

the valve member .32 occupies an upper position with respect to the cylindrical seating surfaced?, with the packing sleeve fl-3 disposed thereabove and within a portion of the housing 29 having a much larger internal diameter than thefexternal diameter of the packing 43, providing an `annular space through which fluid entering the ports 30 .may flow upwardly through the tool, ras well as in a reverse direction (see Figs. l and 2).

Circulating fluids may be pumped down the tubing string I I with the valve in open position, as illustrated in Figs. 1 and 2, passing through the upper annulus ZI and out through the upper ports 2l into a localized Azone 28 between the packing members E53, 66a; thence into the lower ports 21a and lower annular passage 21a, and around the valve packing 43, through the cylindrical seating surface 4l, and the ports 3B to a point below the lowermost packing .member Ela. .The fluid then may proceed upwardly through the by-,pass passage 22a, 20a, I5, 2U, 22 discharging into the. tubing-casing annulus 23 above the upper packing member EI for continued upward movement throughy such annulus to the top of the well bore.

A charge of cement slurry may be started down the tubingstring II and when its lower end is near the well tool, the tubing string may be elevated several inches, say two or three inchs, to move the cylindrical seating surface 47 up over the packing sleeve 43, thus closing the valve and the ports 30 to passage of fluids between the interior of the Well tool and the exterior of the well tool below the lowermost packing Ei Ia. Such relative movement between the valve member 32 and its cooperable cylindrical seating surface M can occur, since the lock pin 39 is disposed within the longitudinal portion 4I of the J-lock slot.

The cement slurry passes from the lower end of the tubularstring II, through the upper annulus ZI in the body and out through the upper ports 21, being forced under pressure through the casing perforations 59 for deposition` behind the Well casing I2. Such cement slurry cannot iiow through the lower ports 21a into the lower body member I4, since the valve is in closed position and the fluid in the lower portions of the body member I d is prevented from passing down- Wardly and out through the ports 30.

Following the deposition of the required amount of cement slurry through the perforations 59, any excess may be flushed from the tool by lowering the tubular string I I, and. the tool body I and valve housing 29 attached thereto, several inches to dispose the horizontal portion dii of the lock slot opposite the `pin 3Q, whereupon the tubular string I I may be turned slightly to the lei-t to cause the lock pin to be located in the upper locking portion d0 of the slot, wherein the valve packing 53 is held elevated above the seating surface M, or in open position. Washing :fluid may then be pumped down the tubular string, forcing the cement slurry ahead of it, and causing it to flow through the upper annulus M, upper port 2l, into the localized zone 28, then through the lower port 27a and lower annulus 2m and around valve packing 43, to discharge through the valve ports 30, whereupon the excess cement slurry, followed by the washing iiuid, may new through the by-pass passage 2120 Zta, iii, 2u, into the annulus 23 above the upper packing EE for passage to the top of the well bore and appropriate disposal.

The ycement slurry may also be disposed of by circulating the washing duid in a direction reversely to that described, by initially pumping it down through the tubing-casing annulus the washing fluid passing through the bymass passage and the ports 3!! for upward flowing around the valve member 32, body 2i 2i and ports 21a, 2l? into the tubing string li, the excess cement slurry in. the tubing string ahead of it to the top of thev Well, bore.

In the event that the excess cement slurry to be disposed of by puni-ping the washing fluid down the tubular string, conditions sometimes render it diiiicult to relatively move the valve member or equivalent valve, to open position. For er.:u ample, in the event that there is an extended column of excess cement slurry present in tubing string of, say, 1,00) feet, the hydrostatic hea-d of such cement slurry acting downwardly on the valve member exerts a downward closing force thereon, which may be substantially greater than the force of friction of the drag springs 3'! against the wall of the well casing I2. Downward movement of the tubing string II and attached body il) and valve housing 29 cannot, therefore, result in openinT of the valve. By virtue of a present invention, the pressure dilerential within a tubing string Il, occasioned by the presence of the high head of cement slurry, does not impose a resultant downward closing force on the valve member 32. i

The pressure acting downwardly on the valve member 32 over the area A is exactly equal to the same pressure acting upwardly on the valve member over the annular area B, such forces being equal and opposite. In other Words, the pressure within the tubing string and within the tool imposes no restraints on the free movement of. the valve member 32 within the valve housing 29 between open and closed positions. Accordingly, with a high head of cement slurry within the tubn ing string H, the latter need merely be lowered several inches to effect relative elevation of the packing member 43 from the cylindrical seating surface 4l, which opens the ports 39 and allows excess cement slurry to be pumped downwardly and out of the tubular string, in the manner described above.

It is to be understood that the areas A and B need not be made exactly equal to each other. As an alternative, the area A may be made slightly greater than the area B, so as to have a resultant force in a downward direction, tending to keep the valve closed in response to pressure in the tubular string and to a body IS. However, it is preferred that the overbalancing hydraulic force in a downward direction on the valve member 32 be less than the frictional force of the drag springs 3l against the wall of the casing l2, to permit the valve to be opened readily whenever desired. On the other hand, the area B may be made greater than the annular area A, in order to cause the fluid pressure within the tubular string li and tool body l to assist in opening of the valve. But, here again, the overbalancing of hydraulic force in an upward direction preferably should not be greater than the frictional force of the drag springs 3"! against the wall of the casing, in order to prevent the internal fluid pressure from inadvertently opening the valve.

Another specific use of the tool described in Fig. l is in connection with the swabbing of the well through casing perforations. Upon the creation of a suction effect in the tubular string relative to the pressure externally thereof, such as through lowering of the uid level in the tubular string the outer packing members 6|, Gla effectively seal the annular Zone 28 therebetween, and prevent fluid in the annuli 23, 23a both above and below the packing cups 6|, 6ml from passing into the localized zone 28. During such swabbing operation, it is desired that the valve be closed and that such suction elect to incapable of opening the valve, such as might occur if the pressure in the lower annular zone 23a around the tool were greater than the pressure within the tubing string and tool body Il).

The arrangement disclosed insures that the valve will remain in closed position. The greater pressure externally of the valve housing acts through the ports 30 in two dierent longitudinal directions on the valve member 32. First, it acts in a downward direction on the piston 49 over the annular area C between the exterior of the Valve body 42 and the wall 48a of the cylinder above the annular piston 49, and it acts in an upward direction over a smaller annular area D between the exterior of the body 42 and the inside surface 4l of the cylindrical seat. In addition, the external pressure acts upwardly over the area E of the rod 3|. Since the annular area C is essentially equal to the sum of the annular area D and rod area E, the pressure externally of the tool has very little, if any, capacity for shifting the valve lll member 32 in either direction during the swabbing operation, and the valve remains in the closed position illustrated in Fig. 3. Accordingly the swabbing operation can take place, without fear of hydraulic forces inadvertently opening the valve and permitting fiuid to flow upwardly therethrough.

A somewhat modied form of valve is disclosed in Fig. 5, which is essentially the same as in the other embodiment of the invention. Instead of a piston type of valve being disclosed as in Figs. 1, 2 and 3, a poppet type of valve member 32a. is illustrated. The valve housing 29, annular piston 49 and cylinder 48 arrangement is essentially the same as in the other modification. The only difference resides in the `provision of a downward Iand inwardly tapering seat 52 in the valve housing 29 above the ports 30, which is adapted to be engaged by a valve head G3 threaded on the upper end of an elongated tubular body 42a. In order to insure against leakage when the head 63 engages the seat 62, an intervening seal ring 64 ma be disposed in the latter.

When the valve member 32a is in open position, its head 63 is disposed above the seat 62 and fluids may ow around the head, and between the interior of the tool body |0 and the ports 3D. When the valve head 63 is in its lower position and engaged with the seat 52 and seal ring 54, the ports 30 are closed and cannot be opened inadvertently by uid pressure.

The ypressure actuatable area F acting downwardly on the valve head 63 is the area across the outermost contact circle between the head and the seal ring 64. The effective area on the valve member 32a in an upward direction is the annular area G between the rod 3| and the cylinder wall 48a, as indicated above in connection with the other embodiment of the invention. This latter annular area, is made equal to the other area F, in order that uid pressure may act on the valve device with equal force both downwardly and upwardly, and thus not tend to shift the valve device in one direction or the other. Of course, as described in connection with the other embodiment, the relationship between the areas can be varied to obtain an overbalanced hydraulic force in one direction or the other, depending upon the eilects desired.

For the purpose of preventing cement or other ingredients from plugging the passage 52 through the valve member body 42, such passage may be provided with a barrier plug 65 slidably mounted therein and carrying a suitable seal ring 66 in a ring groove 61, for preventing fluid leakage in both directions between the `plug and the wall of the body. Upward movement of the plug 55 within the body is prevented by its engagement with an internal flange 68 on the head member 45 while its downward movement is governed by a liquid 69, such as light oil, completely lling the annular cylinder space 53 below the piston 49 and also the passage 42 in the body below the plug 65. This oil may be introduced into the passage and cylinder space through a central hole l in the barrier plug, which is then closed by a suitable pipe plug 1I.

The barrier` plug 65 is oating, or is slidable, within the valve member body 42, transmitting the pressure on its upper surface to the oil 69 in the passage 42 and cylinder space 53. It is thus seen that the same unit pressure on the barrier plug 65 is imposed upon the oil 69, which is eiective for operation upon the annular piston 49 and lower end of the body 42 in the same manner as if the liquid in the well tool Were present within the passage 152 and cylinder space 53 in the `alosence of the barrier plug.

It is apparent that the Iplug 65 prevents the passage 52 from becoming l-led with ce-ment particles ory other :undesired elements, precluding plugging of the passage and insuring transmission ofthe fluid pressure to the underside of rthe ,annular piston 49 and valve member body il?.

Although the valve device has fbeen described with particular :reference to a :tool designed for forcing fluid through casing perforations, it is apparent that it may be applied to other specic tools as well. It is also clear that it may be used in the performance of acidizing, testing, washing, .production and other well bore operations, in Aaddition to the cementing and svvabbing operations specically referred to.

It is, accordingly, apparent that a valvedevice rfor a Well tool has been disclosed, which yis not 'subject to the pressure conditions'with'in the tool tending tomove it from its -desired position within the valve housing. The valve is only moved purposely `when required through manipulation of the ytubing string to .which the well tool is attached.

`Having lthus described my invention, -what I yclaim :and Idesire to secure .by `Letters Patent is:

l. c A well tool, including tubular means having linstrumentaiities for attachment to -a tubular string to .enable the well 'tool to vbe lowered in a well bore, said .tubular means'having an inlet vand an outlet, a Ivalve seat .in said tubular `means -between .said inlet and outlet, a valve lmember mov- .able .longitudinally within said tubular means to and ffrom engagement with said seat to determine 'the -iiow 'of fluid through said outlet, said valve member having a rst fluid lpressure actuatable surface lfacing in one `longitudinal direction and lsubject to the pressure of fluid within said tubular means to tend `to hold said valve member engaged with saidseat, said valve member having ta second yfluid pressure actuatable lsurface disposed on the opposite sideof said outlet vfrein-said seat and subject to uid vpressure toterrd to move said valve member .from said seat,

said valve member rhaving a passage establishing fluidpressure intercommunication between said surfaces when said valve member is vin engagement with said seat and communicating with sai-d inlet and tubular string when said valve member is in engagement with said seat, means for preventing `the uid pressure on the outlet side of said seat from acting onsaid second fluid i pressure actuatable surface when said valve member .is `in engagement with said seat, and means oonnectedto said Vvalve member `for .eiect- .ing .its ,movement to andv from `engagement with said seat.

2. A well tool, including a valve housing embodying instrumentalities for attachment lto a tubularfstring to enable the well tool Ato be 10W- .eredina `well bore, said-housing having anfinlet,

.having a first fluid pressure lactuatable `surface -faeingin one longitudinal direction I,and subject to pressure `.of fluid .within said housing Ito tend f',

to shift said valve means downstream of said jhousing into engagement with ysaid seat, lsaid -valve'fmeans `having -a lpiston slidably engaged piston hav-ing a second fluid pressure actuatabl'e surface facing .in the 'opposite longitudinal direction lto said ,-rst surface, said valve means having a passage establishing iiuid pressure intercommunieation between said .Surfaces when said uvalve means :engages said seat and communicatwith said ,inlet and tubular string when said vaine -ni-eans engages `said seat, said surfaces bw g substantially equal areas in order lthat the pressure acting on said irst surface is talitial-,ly counter-balanced b y the fluid presl @toting :Qn sai-,d rsecond surface, means for prerentirfta iuid pressure on the outlet side of ,said sont from entering said housing for action said r second fguid pressure actuatable surface when fsa/id gvfailve Imeans engages said seat, :and moans for enacting movement of said xvalve .said seat.

n l-1 tool, including a valve housing embodying instrumontaliiies tor attachment to a- ;tubuiar string ato enable the Wel-1 tool t0 4lo@ lowered in :a well vbordea-id ,housing having :an inlet, a .seat land an outlet through ,said housing disnosed longitudinally to one side of :said seatJ o mem-ber in said housing engagea-ble with YSaid seat to prevent-dow of nud between `Saidfernunbol and seat, ,a rod `connected to said member and extending y.tnroi-lg-.n stud housing .in leakfnroof relation with respect thereto, sai-d InQmber `having an annular piston which is fslidobly ensasesble with the inner :wall of saidnousing on the opposite side of `,said outlet from said `seat andinroyding with said rod an ,annular cylinder ,space that .is out of communication with ilud .under pressur-e on the outlet side of said Seat when said member engages said seat, said member vnai/ing a -uid pressure :actuatable Surface :subject to fluid pressure in :said housing wehen fsaiol member engages 'said seat, which `surface is substantially equa-1 infarea tothe :transverse .area of sold annu lar piston in .said annular ycylinder space, said imemberliaving a passage ,establishing 4iiuid `inrossure intercommunication between :said suriaoo and piston when -said :member engages :Said .seat y,and communicating Ywith fsa-id inlet and tubular string when said v member engages said seat, and means connected to :said rod ;for effecting movement of said member to and 1from said seat.

o. A well tool, including a vvalve housing ernbodving instrumentalities for .attachment to ,a ftubular string to `enable the well tool to belowcred in :a .well bore, said :housing :having an zinlet, aseat andan-outlet disposed `below said seat, a member in said housing movable .downwardly into engagement nwithtsaid seat, a rod connected ;to .said member and ,extending downwardly through :said 'rhousing in leakproof :relation .with ire-speci; thereto, y'said member v:having an ,annular :piston ,which iis lslidably :engagea-ble with `the finner wall .of `said :housing below said outlet .and providing .with :said trod an annular 4cylinder vspace 'that 'is out :of `communication with fluid under .pressure von the outlet side of said 4seat when :said` member engages :said seat, lsaid member yhaving a :passage establishing fluid =pressure inter-communication between :an upwardly facing fluid .pressure .-actuatable surface on said rmember and said :cylinder space :below -said :piston when said 4member iis ,in engagement i,with said seat, :said passage 4.oomrnurlisa-ting .with said Ainlet .and .tubular string rwhen ,saidfrnember iis ,in I,engage- .vmentlwithtsaidfseot and moans connected tofsaid rod ifor lenicotine movement of said member rto andromsaid seat.

with lsai-d 1housing to one side orsaidseat, ,said 7x5 A5,. .A well packen .including a hollow :body

adapted to be connected to a tubular string for lowering in a well casing; said body having packing means thereon for effecting a seal with the wall of said casing; valve means for controlling fluid flow in said body, comprising a valve housing secured to said body and having an inlet, a seat and an outlet disposed below said seat, a member in said housing movable downwardly into engagement with said seat, a rod connected to said member and extending downwardly through said housing in leakproof relation with respect thereto, said member having an annular piston which is slidably engageable with the inner wall of said housing below said outlet and providing with said rod an annular cylinder space that is out of communication with the fluid under pressure on the -outlet side of said seat when said member engages said seat, said member having a passage establishing fluid pressure communication with an upwardly facing fluid pressure actuable surface on said member and said cylinder space below said piston when said member engages said seat, said passage communicating with said inlet and tubular string when said member is in engagement with said seat; and means connected to said rod and engageable with said casing for resisting movement of said member upon movement of said body and housing.

6. A well packer, including a hollow body adapted to be connected to a tubular string for lowering in a well casing, said body having packing means thereon for effecting a seal with the wall of said casing, a valve housing secured to the lower end of said body and having an inlet and an outlet and a valve seat between said inlet and outlet, a valve member engageable with said seat, said valve member having oppositely facing pressure actuable surfaces of substantially equal areas, one of said surfaces communicating with said inlet-and hollow body when said valve member engages said seat, means for preventing the fluid pressure on the outlet side of said seat from acting on said other surface when said valve member engages said seat, said valve member having a passage therein communicating with said' inlet and hollow body and establishing fluid pressure intercommunication between said surfaces, in order that fluid under pressure within said housing can act simultaneously upon said oppositely facing surfaces when said valve member engages said seat; and means for effecting movement of said valve member to and from said seat.

7. A well packer, including a hollow body adapted to be connected to a tubular string for lowering in a well casing, said body having longitudinally spaced packing means thereon for effecting a seal with the wall of said casing, ports in said body establishing communication between the interior of said body and its exterior between said packing means, valve means for controlling flow of fluid in said body through said ports, comprising a valve housing secured to said body and having an inlet and an outlet and a valve seat between said inlet and outlet, a valve member engageable with said seat, said Valve member having oppositely facing fluid pressure actuatable surfaces of substantially equal areas, one of said surfaces communicating with said inlet and hollow body when said valve member engages said seat, means for preventing the fluid pressure on the outlet side of said seat from acting on said other surface when said valve member engages said seat, said valve member having a passage therein communicating with said inlet and hollow body and establishing fluid pressure intercommunication between said surfaces in order that fluid under pressure within said body and housing can act simultaneously upon said oppositely facing surfaces when said valve member engages said seat, and means for effecting movement of said valve member to and from said seat.

8. A well packer, including a hollow body adapted to be connected to a tubular string for lowering in a well casing, said body having longitudinally spaced packing means thereon for effecting a seal With the wall of said casing, ports in said body establishing communication between the interior of said body and its exterior between said packing means, valve means for controlling flow of fluid in said body and through said port, comprising a valve housing secured to said body and having an inlet, a seat and an outlet disposed below said seat, a member in said housing movable downwardly into engagement with said seat, a rod connected to said member and extending downwardly through said housing in leakproof relation with respect thereto, said member having an annular piston which is slidably engageable with the inner wall of said housing below said outlet and providing with said rod an annular cylinder space that is out of communication with fluid under pressure on the outlet side of said seat when said member engages said seat, said member having a passage establishing fluid pressure communication between an upwardly facing fluid pressure actuatable surface on said member and said cylinder space when said member engages said seat, said passage communicating with said inlet and tubular string when said member is in engagement with said seat, and means connected to said rod and engageable with said casing for resisting movement of said member upon movement of said body and housing.

9. A well tool, including tubular means adapted to be lowered in a well bore and having an inlet and an outlet, a valve seat in said tubular means between said inlet and outlet, a valve member movable longitudinally to and from engagement with said seat to determine flow of uid therethrough, said valve member having oppositely facing transverse fluid pressure actuatable surfaces, one of said surfaces communicating with said inlet when said valve member engages said seat, means for preventing the fluid pressure on the outlet side of said seat from acting on said other surface when said Valve member engages said seat, said valve member having a passage therein communicating with said inlet and establishing fluid pressure intercommunication between said surfaces in order that fluid under pressure within said tubular means can act simultaneously upon said oppositely facing surfaces when said valve member engages said seat, means for effecting movement of said valve member to and from said seat, and a movable barrier across said passage for transmitting the pressure of the fluid externally of the passage t0 fluid internally of the passage.

10. A well tool, including tubular means adapted to be lowered in a well bore on a tubular string and having an inlet and an outlet, a valve seat in said tubular means between said inlet and outlet, a valve member movable longitudinally to and from engagement with said seat, said valve member having a first fluid pressure actuatable surface facing in one longitudinal direction and subject to the pressure of fluid in the inlet within said tubular means and tubular string above said valve member to tend to hold said valve member engaged with said seat, said valve member having a second fluid pressure actuatable surface facing in the opposite 1ongitudinal direction and subject to fluid pressure to tend to move said valve member from said seat, said valve member having a passage establishing fluid pressure intercommunication between said surfaces when said valve member is in engagement with said seat and communicating with said inlet and tubular string when said valve member is in engagement with said seat, means for preventing the fluid pressure on the outlet side of said seat from acting on said second fluid pressure actuatable surface when said valve member is in engagement with said seat, means connected to said valve member for effecting its movement to and from engagement with said seat, and means disposed across said passage to prevent substantial entry of undesired substances there-into.

11. A well tool, including tubular means hav-ing instrumentalities for attachment to a tubular string to enable the well tool to be lowered in a Well bore, said tubular means having an inlet and an outlet, a valve seat in said tubular means between said inlet and outlet, a valve member engageable with said seat, said valve member having a transverse surface facing upstream and subject to the fluid pressure in said tubular means on the upstream side of said valve member to urge said valve member toward engagement with said seat, said valve member having a surface facing downstream, said valve member having a passage therein establishing fluid pressure intercommunication between said surfaces in order that fluid under pressure within said tubular means upstream of said valve member can act simultaneously upon said oppositely facing surfaces when said valve member engages said seat, said passage communicating with said inlet and tubular string when said valve member is in engagement with said seat, means for preventing the ud pressure on the outlet side of said seat from acting on said surface facing downstream when said valve member is in engagement with said seat, and means for effecting movement of said valve member to and from engagement with said seat.

12. A well tool, including tubular means adapted to be lowered in a well bore and having an inlet and an outlet, a valve seat in said tubular means between said inlet and outlet, a valve member movable longitudinally to and from engagement with said seat to determine flow of fluid therethrough, said valve member having oppositely facing transverse fluid pressure actuatable surfaces of substantially equal areas, one of said surfaces communicating with said inlet and tubular means when said valve member engages said seat, means for preventing the fluid pressure on the outlet side of said seat from acting on said other surface when said valve member engages said seat, said valve member having a passage therein communicating withsaid inlet and tubular means and establishing fluid pressure intercommunication between said surfaces in order that fluid under pressure Within said tubular means can act simultaneously upon said oppositely facing surfaces when said valve member engages said seat, means for effecting movement of said valve member to and from said seat, and a barrier slidable in said passage to transmit the pressure of the uid on one side of the barrier to the uid on the other side of said barrier within the passage.

BERNARD KRIEGEL.

References Citedin the file of this patent UNITED STATES PATENTS Number Name Date 951,172 Biedenmeister Mar. 8, 1910 1,720,705 Waterman July 16, 1929 2,054,606 Smith Sept. 15, 1936 2,092,338 Spencer Sept. 7, 1937 2,301,624 Holt Nov. 10, 1942 2,326,940 Granger Aug. 17, 1943 2,466,305 Costello Apr. 5, 1949 

